Non-catalyst Ceramic Fiber Filter
Dedusting:
The dedusting filter bin is divided into upper and lower parts. The lower part is the air inlet filter bin, and the upper part is the air outlet clean bin. The upper and lower bins are separated by a perforated fixing plate. The ceramic fiber filters are suspended vertically on the holes of the fixing plate. After the high temperature dusty gas enters into the air inlet filter bin, under the action of the high temperature induced draft fan, it goes through from the outside wall of the ceramic fiber filter into the inside filter, and then it is discharged from the inside filter to the air outlet clean bin(figure 1).
At this time, the dust in the gas will be blocked on the outside wall of the ceramic fiber filter, and the dust cake on the outside wall of the filter will become thicker and thicker. Only the clean gas could go through the wall of the filter into the inside filter (figure 2).
As the dust cake accumulates thicker and thicker on the outside wall of the ceramic fiber filter, the resistance of the filter will become larger and larger, and so does the internal and external pressure difference of the filter. At this time, the system will start backflush cleaning program. The compressed air will be blown back into the ceramic fiber filter. The dust cake on the outside wall of the filter will fall off(figure 3). Then the ceramic fiber filter can start a new round of dust removal procedures.
Please refer to the figure below:
Catalytic Ceramic Fiber Filter
Desulfurization and de-acid gas（HCl/HF）
Lime or NaHCO3 can be used to react with acid gas. The reactants (solid compounds) will be left on the outside wall of the filter when it goes through the filter, while the harmless gas will be discharged from the chimney. This process is similar to the dedusting process. The reaction equations are as follows:：
NaHCO3+SO2=NaHSO3+CO2（SO2少量）
NaHCO3+HCL= NaCl+CO2+H2O
NaHCO3+HF= NaF+CO2+H2O
Remark: In the actual working conditions, it is rare to have desulfurization alone. Usually, desulfurization and denitrification are carried out at the same time. At this case, the catalytic ceramic fiber filters are needed.
Denitrification:
The denitrification reaction could be accelerated by adding a catalyst to the wall of the ceramic fiber filter. With traditional technology, Liquid ammonia or Urea /CO(NH2)2 are added to react with NOx. The reaction formulas are as follows:
4NO+4NH3+O2 ＝ 4N2+6H20
2NO2+4NH3+O2 ＝ 3N2+6H20
4NO+2(NH2)2CO+O2 ＝ 4N2+4H20+2CO2
De-dioxins:
The catalyst in the ceramic fiber filter can not only catalyze the removal of the nitrogen oxides (NOx), but also can catalyze the removal of Dioxins. Under the action of the catalyst, dioxins react with oxygen to produce non-toxic substances such as CO2, H2O and HCl. The reaction equation is as follows:
C12HnCl8-nO2＋(9＋0.5n)O2→(n-2)H2O＋12CO2＋(8-n)HCl
ü Up to 99.9% dust removal
ü Up to 97% HCL removal
ü Up to 95% SOx removal
ü Up to 95% NOx removal
ü Up to 97% dioxin removal
